July 1, 1999AJP Heart and Circulatory Physiology
Nonuniform responses of transmembrane potential during electric field stimulation of single cardiac cells
Key result
Electric field stimulation of isolated guinea pig ventricular myocytes produced a biphasic transmembrane potential response that varied nonlinearly with field strength and polarity.
Population
Isolated guinea pig ventricular myocytes stained with a voltage-sensitive fluorescent dye, di-8-ANEPPS
Design
Preclinical
Authors
Discussion
Loading...
Member takes
Overview
Challenges models of defibrillation currents; leaves open translation to intact human hearts.
Structured PICO
P
Population
Isolated guinea pig ventricular myocytes stained with a voltage-sensitive fluorescent dye, di-8-ANEPPS (10 microM)
I
Intervention
Electric field stimulation directed along the long axis of the cell (30-ms S1-S2 coupling interval, 10-ms S2 pulse up to ~500-mV half-cell length potential)
O
Outcome
Subcellular transmembrane potential (Vm) response measured opticallysurrogate
The nonlinear transmembrane potential response to electric fields in cardiac myocytes suggests the involvement of electroporation and non-physiological outward currents during pacing and defibrillation.
Cite This Study
Cheng et al. (1999) studied Isolated guinea pig ventricular myocytes. Electric field stimulation was evaluated on Cellular transmembrane potentials (V(m)) response. Electric field stimulation of isolated guinea pig ventricular myocytes produced a biphasic transmembrane potential response that varied nonlinearly with field strength and polarity.